How the retirement estimate works

The calculator is an educational first look. It deliberately shows its assumptions so you can understand what the result means—and what it does not mean.

Projection to retirement

Current retirement savings grow from the current age to the selected retirement age using a 5% annual real return. “Real” means after inflation, so inputs and results remain in today's purchasing power. Monthly contributions are added throughout that period.

Estimated retirement income

The projected balance is multiplied by a 4% starting annual withdrawal guideline and divided by twelve. The calculator then adds the monthly Social Security and pension estimate plus any additional monthly income entered by the user.

Coverage percentage

Estimated monthly income is divided by the monthly retirement-spending target. A result of 100% means the estimate equals the entered target under these assumptions. It does not represent a probability of success.

Why 5% is not labeled universally conservative

A 5% return after inflation may be moderate for one investment mix and aggressive for another. Returns are uneven, fees and taxes matter, and the order of market returns can materially affect a retiree taking withdrawals. The estimate is neither a forecast nor a promise.

How the weekly What-If Labs work

Each lab isolates one planning relationship so the effect is easy to see. Sliders update the numbers and code-drawn picture in the browser. A lab may use a constant return, a 4% starting-withdrawal illustration, or another clearly labeled simplification. Those relationships are teaching devices, not forecasts or personalized recommendations; each lab states its own exclusions beside the interactive result.

What the first-look calculator does not yet model

• Federal or state taxes and account-specific tax treatment
• Market volatility or sequence-of-returns risk
• Social Security claiming-age adjustments or survivor benefits
• Health-insurance costs, Medicare premiums, or long-term care
• Required distributions, Roth conversions, or withdrawal ordering
• Changing spending phases, fees, or a detailed longevity range

How to use the result

Use the result to identify the next question: spending, retirement age, saving rate, guaranteed income, or another income source. Before making an irreversible retirement, investment, insurance, tax, or legal decision, validate the plan with qualified professionals who can evaluate the complete household.